This section provides background information to facilitate a better understanding of the various aspects of the disclosure. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.
Enclosed conveyor belts, often referred to as pipe or tube conveyors, are conveyor belts which are typically loaded with a material to be conveyed by the belt when the belt is in a flat, open or troughed state. After having the material to be conveyed deposited thereon, the belt can, for example, convey the material in a troughed state or be closed into a tubular- or pipe-shaped configuration.
Antennas can be embedded into conveyor belts for the purpose of detecting damage to the belt. The antennas are oriented such that they run across the conveyor belt transverse to the longitudinal direction of the belt and the direction of travel of the belt. A transmitter for generating an electromagnetic field in the antenna and a detector for detecting the electrical field generated or induced in the antenna by the transmitter are disposed together at a longitudinal position of the conveyor belt system such that the detector and transmitter are adjacent to each other at a spaced relationship with respect to the transverse direction of the belt.
The implementation of such antennas in pipe belt conveyors has been largely ineffective due to cross-talk across the conveyor belt. Cross-talk can occur when a transmitter for inducing an electrical field in an antenna inductively couples directly to a detector that is meant to detect the coupled electrical field induced in the passing antenna. Conveyor belts can also have internal structures which can contribute to an undesirable coupling of the transmitter and the detector. Given that most, if not every, conveyor belt and conveyor structures are different, the strength of a cross-coupled signal can vary with each installation.